The Department of Health and Human Services said a neurosurgical patient at the hospital is suspected to have had sporadic Creutzfeldt-Jakob disease. The disease is caused by a prion, a type of protein that isn't folded in a normal way.

Health officials said prions aren't eradicated during normal sterilization procedures, so it's possible that other patients could have been exposed to the illness through neurosurgical procedures.

"The risk to these individuals is considered extremely low, but after extensive expert discussion, we could not conclude that there was no risk, so we are taking the step of notifying the patients and providing them with as much information as we can," said Dr. Jose Montero, director of public health. "Our sympathies are with all of the patients and their families, as this may be a confusing and difficult situation."

The disease has only been transmitted through surgical equipment four times, and never in the United States, health officials said. Some of the surgical instruments had been rented, so officials said up to five patients in other states may also have been exposed.

One New Hampshire man said the disease killed his sister 14 years ago.

“She didn’t know where she was, what she was doing, what her name was,” said Robert Blodgett of Epsom.

Blodgett said the final days of his sister’s life were heartbreaking. Shirley Cummings was born and raised in Penacook. In the summer of 1999, her family noticed she started losing her memory and her behavior was off.

“It’s fast,” Blodgett said. “It’s dementia in fast-forward.”

His sister died eight weeks after being diagnosed. She was 63.

Blodgett said he was stunned when he hear eight patients may have been exposed in Manchester.

“I said, ‘Look at that, that’s what Shirley had,’” Blodgett said.

To this day, Blodgett said he wonders how his sister got the disease.

“Not knowing how she got it, that’s the biggest thing,” he said.

Officials said sporadic Creutzfeldt-Jakob disease happens spontaneously, with no known trigger. It's different from variant Creutzfeldt-Jakob disease, also known as mad cow disease, which is transmitted by eating contaminated beef.

Creutzfeldt-Jakob disease is a rare and fatal disease that affects the nervous system and causes deterioration of the brain. It affects about one in a million people each year worldwide, health officials said. In the United States, only about 200 people are diagnosed with CJD each year.

The disease causes progressive cognitive problems and personality changes, along with coordination difficulties. Eventually, mental deterioration becomes pronounced, and patients may develop involuntary, jerky movements. There is no treatment or cure.

"Our concern is with the health and well-being of the eight patients who may have been exposed to CJD," said Dr. Joseph Pepe, president and CEO of CMC. "We will work closely with these families to help them in any way possible, even though the risk of infection is extremely low."

The only way to definitively diagnose Creutzfeldt-Jakob disease is through an autopsy, which is underway on the original patient, health officials said.

“There is no risk to any other patients, their families or the general public,” said Tim Soucy, Manchester’s health director.

The equipment used in neurosurgery at CMC has been quarantined and brain surgery at the hospital has been put on hold, officials said.

LIKE WE DO, IN HIGH DEFINITION, NOW WMUR NEWS 9 TONIGHT. EIGHT PEOPLE WHO HAD BRAIN SURGERY AT CATHOLIC MEDICAL CENTER IN MANCHESTER ARE NOW BEING WARNED THEY COULD HAVE BEEN EXPOSED TO AN EXTREMELY RARE AND DEADLY BRAIN DISEASE. GOOD EVENING, I'M SHELLEY WALCOTT. TOM GRIFFITH IS OFF. THE WARNING WAS TRIGGERED BECAUSE A PATIENT WHO APPARENTLY DIED FROM SPORADIC CREUTZFELDT-JAKOB DISEASE HAD SURGERY THERE, AND THERE'S A POSSIBILITY THAT SURGICAL INSTRUMENTS WERE CONTAMINATED BECAUSE STANDARD STERILIZATION DOES NOT WORK WITH THIS DISEASE. OUR JEAN MACKIN JOINS US LIVE WITH THE RISK TO THOSE PATIENTS AND HOW ONE FAMILY HAS BEEN DEEPLY IMPACTED BY THIS DISEASE. TODAY HEALTH EXPERTS STRESSED THE RISK OF THOSE EIGHT PATIENTS CONTRACTING CJD IS EXTREMELY LOW, CLOSE TO ZERO, BUT THEY ARE BEING WARNED JUST IN CASE. ONE NEW HAMPSHIRE MAN SAYS HIS RAPIDLY DEGENERATIVE NEUROLOGICAL DISEASE TOOK HIS SISTER 14 YEARS AGO. SHE DIDN'T KNOW WHERE SHE WAS, WHAT SHE WAS DOING, WHAT HER NAME WAS. ROBERT BLODGETT SAYS THE FINAL DAYS OF HIS SISTER'S LIFE WERE HEARTBREAKING. SHIRLEY CUMMINGS PASS BORN AND RAISED IN PENACOOK. SHE STARTED LOSING HER BEHAVIOR, HER BEHAVIOR WAS OFF. ROBERT NOW COLLECTS RESEARCH AFTER HE SAYS HIS SISTER WAS DIAGNOSED WITH CREUTZFELDT-JAKOB DISEASE, OR CJD, AN EXTREMELY RARE AND INCURABLE DISEASE THAT ATTACKS THE BRAIN. IT'S FAST, IT'S DEMENTIA IN FAST FORWARD. SHE DIED EIGHT WEEKS AFTER BEING DIAGNOSED. SHE WAS 63 YEARS OLD. ROBERT WAS STUNNED WHEN HE HEARD EIGHT NEUROSURGERIRY PATIENTS MAY HAVE BEEN EXPOSED AT CATHOLIC MEDICAL CENTER IN MANCHESTER. I SAID LOOK AT THAT, THAT'S WHAT SHIRLEY HAD. THEY SAY WHILE THE RISK OF TRANSMISSION IS EXTREMELY LOW, PATIENTS MAY HAVE BEEN EXPOSED THROUGH SURGICAL EQUIPMENT. EQUIPMENT USED ON A PATIENT WHO LATER DIED FROM CJD, A DISEASE THAT RESISTS STANDARD STERILIZATION. THERE HAVE ONLY BEEN FOUR CASES IN THE WORLD LITERATURE OF THIS TYPE OF TRANSFER. THERE IS NO RISK TO ANY OTHER PATIENTS, THEIR FAMILIES OR THE GENERAL PUBLIC. CJD INFECTONE IN A MILLION PEOPLE WORLDWIDE EACH YEAR, ABOUT 200 IN THE UNITED STATES. NO CAUSE HAS BEEN PINPOINTED. THERE'S NO TREATMENT, NO CURE, NO SCREENING TEST. TO THIS DAY, ROBERT WONDERS HOW HIS SISTER GOT IT. NOT KNOWING HOW SHE GOT IT, THAT'S THE BIGGEST THING. EQUIPMENT USED IN NEUROSURGERIRY AT C.M.C. HAS BEEN QUARANTINED AND FOR THE TIME BEING BRAIN SURGERY HAS